The duo arrested for allegedly trafficking a two-day-old baby last Sunday had recently visited Maldives and Congo raising suspicion about whether the racket was an overseas one.

The state CID probing the human trafficking case has found links between this racket and another child racket that was busted in Narendrapur last year.

Senior officers of the CID said the agency would take up the probe of the Narendrapur child trafficking case.

Last year, a couple was arrested from Narendrapurfor allegedly selling their baby for ₹2 lakh. The “deal”was allegedly fixed before the childbirth.

The Baruipur police district under whose jurisdiction Narendrapur falls, had arrested the couple and another woman who was instrumental in the alleged sale of thenewborn.

Investigators had also located a small nursing home in a remote village in Usti, South 24-Parganas, through which such alleged deals were struck.

In this case, Manik Haldar, 38, and Mukul Sarkar, 32, from Thakurpukur, were arrested for trying to sell a baby for ₹4 lakh near Shalimar railway station on Sunday. They had allegedly purchased the baby for ₹1 lakh from Patna.

“We are verifying all the leads. We have identified a woman who is most probably the child’s mother,” said an officer at Bhabani Bhavan.

“We are also looking into the duo’s recent visits to Maldives and Congo and if found suspicious, we will probe if the racket could have been an overseas one.”

The duo had used social media to get clients — childless couples who were ready to shell out money to get a baby.

In a city where many still cannot afford one square meal a day and are forced to live under flyovers, handing children to a relative or an acquaintance for “better upkeep” is not uncommon. However, once the parents accept money for their child, it becomes “human trafficking”.

“Even if there is an exchange of money, such cases are rarely reported to the police as neither the parents nor the people who take the child ever complain,” said an officer.

Couples or individuals who wish to adopt a child have to formally go through a process of adoption governed by the central government’s ministry of women and childdevelopment.